[[File:Lightwarp heavy.png|thumb|150px|It is the cornerstone of TF2's illustrative character rendering.]]

[[File:Lightwarp heavy.png|thumb|150px|It is the cornerstone of TF2's illustrative character rendering.]]

[[File:Lightwarp BW.png|thumb|150px|Posterised colour can be achieved, but lighting must be tightly controlled.]]

[[File:Lightwarp BW.png|thumb|150px|Posterised colour can be achieved, but lighting must be tightly controlled.]]

+

[[File:Celshadingpreview.png|thumb|250px|Cel shading in action.]]

+

'''<code>$lightwarptexture</code>''' is a [[material]] parameter that tints [[texel]]s depending on their brightness. It can be thought of as localised [[color correction]]. It requires at least [[DirectX]] 9.

'''<code>$lightwarptexture</code>''' is a [[material]] parameter that tints [[texel]]s depending on their brightness. It can be thought of as localised [[color correction]]. It requires at least [[DirectX]] 9.

Line 26:

Line 28:

:This custom warp texture creates a posterised "line art" style. Enabling lightwarp alone isn't enough however: ambient lighting must be at 0 to make unlit areas black, and world lighting must become viewer-dependent to ensure that shadows are always cast.

:This custom warp texture creates a posterised "line art" style. Enabling lightwarp alone isn't enough however: ambient lighting must be at 0 to make unlit areas black, and world lighting must become viewer-dependent to ensure that shadows are always cast.

−

Other possible uses of <code>$lightwarptexture</code> include toon shading, contrast enhancement and highlight softening.

+

; <code>Cel Shading</code>

+

: [[File:Cel_lightwarp.png|border|Custom texture]]

+

:Cel shading can make objects look more cartoony, by replacing the smooth lighting gradient with sharp steps.

Lightwarp textures

A lightwarp texture is a one-dimensional strip of pixels. Dark texels will be tinted with the colour on the left-hand side, and bright texels with the colour on the right. 50% gray means no tint.

Examples

snow_warp

This is the lightwarp texture used in the DOD Source screen to the right. It is designed to add a subtle bluish tint to darker snow, without affecting brighter regions.

pyro_lightwarp

This is applied to all TF2 characters, not just Pyro. It creates the high-contrast shadows with red-tinged terminators typical of the illustrative art the game apes.

Posterised

This custom warp texture creates a posterised "line art" style. Enabling lightwarp alone isn't enough however: ambient lighting must be at 0 to make unlit areas black, and world lighting must become viewer-dependent to ensure that shadows are always cast.

Cel Shading

Cel shading can make objects look more cartoony, by replacing the smooth lighting gradient with sharp steps.